A Police Mobile Brigade (Brimob) officer teaches a student how to use a tear gas rifle during a 'Bela Negara' (Defend the Nation) training in Malang, East Java, on Wednesday (04/01). (Antara Photo/Ari Bowo Sucipto)

A police Mobile Brigade (Brimob) officer teaches a student how to use a tear gas rifle during a "Bela Negara" (Defend the Nation) training in Malang, East Java, on Wednesday (04/01). (Antara Photo/Ari Bowo Sucipto)